A fuel reforming device, commonly known as a steam reforming device, is a type of reformer that generates hydrogen by reforming a raw gas, such as liquefied natural gas (LNG) and liquefied petroleum gas (LPG).
A steam reforming device typically includes a steam reformer, also referred to as a reforming reactor, for generating hydrogen from a raw gas. For example, if the raw gas is LNG having a main component of methane (CH4), then the stream reformer reacts the CH4 with steam to generate hydrogen and carbon dioxide.
However, if carbon monoxide flows into a fuel cell stack, then the stack may be contaminated by carbon monoxide, whereby performance of the stack may be degraded. Therefore, carbon monoxide generated through the steam reformer is often shifted to carbon dioxide by using a shift reactor, such as a high temperature shift reactor (HTS) and a low temperature shift reactor (LTS).
As such, a steam reforming device typically includes a shift reactor, such as a HTS and LTS, for shifting carbon monoxide (CO) generated with hydrogen to carbon dioxide (CO2) to lower concentration of the carbon monoxide.
In addition, some steam reforming devices include a burner for supplying calories. An operation temperature in the steam reformer may be different depending on a type of catalyst that is used. For example, if Ni is used as a catalyst, the operation temperature is generally in the range of 600° C. to 700° C., and this reaction is an endothermic reaction. The calories required for this endothermic reaction are supplied using the burner. An operation temperature in the shift reactor is also different depending on the type of the catalyst, wherein the operation temperature is generally in the range of 300° C. to 420° C. in case of a high temperature shift reactor based on Cu—Zn, and is generally in the range of 235° C. to 300° C. in case of a low temperature shift reactor based on Fe—Cr. This shift reaction is an exothermic reaction and radiates heat during reaction.